Your aging air conditioner has frozen up, and your HVAC technician just diagnosed a refrigerant leak in the system. When this situation arises for our Homesense clients, we don’t recommend that more expensive refrigerant be dumped into a system with known leaks, even though they do often ask us to add one pound of freon to help situation. Instead, we highly encourage a leak test be conducted to potentially fix the leak before adding any more refrigerant to the system. Most HVAC service technicians keep an electronic leak detector or sniffer in their toolkits. As the name suggests, the HVAC tech runs this tool along the refrigeration components to detect any R22 or R410a outside of the system. Most HVAC technicians will start a leak test by using this device, as it can be more cost effective in finding a leak. The limitation to an electronic leak detector test is that it can only scan the components it can touch. With an evaporator coil leak, for example, it can be quite difficult to position the electronic leak detector in all places a potential leak might be.

So while this can be the most cost effective leak test, it is also the most prone to inaccuracy.thru wall ac/heater units A nitrogen leak detector test—the preferred test by Homesense technicians—adds a greater degree of clarity to leak detection, though for slightly more cost.in wall air conditioning and heating units With this test, the HVAC technician first removes any remaining freon or Puron and pumps compressed nitrogen into the refrigeration system. air conditioner unit power consumptionThe leaks become audible because the nitrogen is held at a higher pressure than the refrigerant can operate under normal conditions. Imagine when you pump air into your bicycle tire, and you can hear the air coming out.

It’s the same concept here. In addition to listening for audible signs of a leak, HVAC technicians will also be watching the gauges to see if pressure changes. In a system without leaks, pressure will remain constant. A system with a leak will show fluctuations. Also, the technician will many times take the additional step of “bubbling” the system. The technician will mix up soap bubbles, run it along components of the refrigeration system, and look for air bubbles. A dye test for freon or Puron leaks can also be applied. Here, an HVAC technician adds ultraviolet dye to the system, looking for both constant and intermittent leaks. The UV dye mixes with lubricants within the system and finds its way to even the smallest leaks. The technician uses a blue/black light to see the dye as it leaks out. It’s important to note that not all dyes are recommended by manufacturers and can have negative consequences on the air conditioning system if the dye is not supported.

Air Conditioning, Heating and Cooling FAQs, HVAC IndianapolisAn auto air conditioning leak is probably the most common problem found when your car AC system isn't blowing cold air. The temperature at the dash vents should be in the 45-55 degree range. can happen is the Freon will leak out and reduce the total pressure in the system. Then the low-pressure cut-off switchMost car makers turn off the compressor when the low side is detected below 25 PSI. safety feature to protect the component from harm. professional and driveway mechanics bypass the low cut-off switch forThis diagnostic step is not recommended. Damage to the compressor happens quickly when the freon is low, because the refrigerant contains a lubricant charge. damage occurs it wreaks havoc by spreading tiny metal flakes throughout the entire airFor these reasons replacing the compressor is an expensive auto repair. Note that when the system pressure is low and the clutch disengages, it's just

like having the AC switch turned to the off position.Therefore, leak testing is one of the most important tasks when it comes to troubleshooting a system. Keep in mind that over a long period of time all air conditioners will lose or leak out some refrigerant. I went to a Delco AC training class and the instructor said, an automotive air conditioner could lose up to 2 ounces of Freon a year and this is considered normal. As I mentioned before in previous articles about how the air-conditioning system works, the Freon contains the lubricating oil charge necessary to protect the compressors internal moving parts. can also use this refrigerant oil to find leaks. The visual presence of oil around a fitting or pressurized line is a strong indication of a leak. So my first step in diagnosis is to perform a careful visual inspection of the entire system. this is my first step, it's not always effective in pinpointing the issue. In fact, this visual

inspection will only uncover large problems and having a small leak is more common. These slow leaks allow refrigerant to escape over long periods ofNext we'll highlight some methods for locating these hard to find issues. My Robinair and TIF instruments leak detectors are the second tools I'll use in my fight against air conditioning leaks. is the preferred method of refrigerant  detection, because it's safe, effective and compatible with many types of Freon. These detectors are a hand held battery operated electronic gas sniffer. on the end is moved about 1 inch per second in the areas of suspected leaks. Make sure there is a partial charge in the system and the tester tip is clean before beginning. I usually go for the high pressure side fittings andThe refrigerant gas is heavier than air. Therefore, I run the leak detector just below these fittings and lines. Robin air leak detector has an alarm that goes off when it detects the presence of a refrigerant.

Note on some other models they may have flashing lights or a buzzer. Also some cheaper leak detectors onlyPeople make a few common mistakes when leak testing AC systems with these leak sniffers. First, they get impatient and move the tip too quickly. Second, is failure to run the tester lead under the component connections and lines. Finally, the tip attracts dirt easily. You have to keep the tip clean or they won't do their job right. Most auto repair shops I've worked at, including the one I work at now, has a fluorescent dye tracer system for finding stubborn leaks. To find refrigerant leaks using the fluorescent tracer system, you first have to install the fluorescent dye into the AC system. Always follow the instructions and do not install too much dye. This is important, because too much can reduce the cooling efficiency of the system. refrigerant dye leak detectors will accomplish this in different ways. The type we use at work has a device that looks like a caulking gun

and a hose that connects to the low side fitting. Then you actually push the dye into the low side with the engine running and the compressorNext you run the air-conditioning system for several minutes to distribute the dye evenly. Then you put on your yellow glasses and examine the system with a fluorescent light. The fluorescent dye shows up easily wearing the yellow glasses. Sometimes the results will yield something you don't want to find. example, the last time I used the fluorescent dye system I didn't see any leaks in the engine compartment. However, when I examined the evaporator case inside the passenger cabin, the fluorescent dye formed a large puddle at the bottom of it. This meant the evaporator itselfThis isn't a fun job on most automobiles. On many models the dash has to come out completely to access it. A very popular selling item is refrigerant with leak sealer. This item will only seal very small leaks. I have used the stuff

pictured to the right called "super seal pro" and it does work in isolatedIt works best when you have low pressure side system problems. If you happen to have a small leak from an O-ring on the low side, this stuff can work well. However, if you have an issue on the high-pressure side chances are this sealer won't work for you. If the leak is small enough and from an O-ring on the high side there is a 50-50 chance the stop leak will help. Although, when I say help, I mean it might slow it down even further, but it will most likely continue to leak. An example of common results from using an air conditioner leak sealer is it still leaks, but may require less recharging. If your lucky a charge installed in the spring will last till the end of the summer in the best-case scenarios. Nevertheless, with the cost of AC repairs quickly becoming one of the most expensive auto repairs of all, $50 a year to stay cool seems like it's worth a try.

Just remember I mentioned it may not work at all and you'll wind up having to diagnose your air conditioning leaks the old fashioned way. It's quite possible that physical repairs or the replacement of AC components will be required. decide to go ahead and replace ac parts it's important to pull a vacuum on the system to remove any moisture after the repairs areMoisture can cause many problems, but can also freeze up and create hard to diagnose blockages in the system. Give this automobile AC repair page a bookmark or share. Then come back to explore the additional information on this subject available below. I'm a strong believer that it is easier to fix something when you understand how it works fully. And this is what the car AC section of this website is all about. This next link will take you to the automotive air-conditioning repair module. My best page about this subject provides information about protecting yourself from common rip-off car AC repairs.